What is cholesterol and how do I check it?

More than two in five people in England have high cholesterol. But with few signs or symptoms, how do you know if you've got high or normal cholesterol?

Earlier this year, the NHS announced that more than two in five people in England have high cholesterol, putting them at significant risk of developing heart and circulatory diseases, including heart attack and stroke [1].

But there are simple things you can do to help bring your cholesterol down to a healthy level. So, let’s have a look at the different types of cholesterol, how to check your cholesterol and how you can lower bad cholesterol.

What is cholesterol?

Cholesterol is a fatty substance in our blood, produced naturally in the liver. Everyone has cholesterol because every cell in our body needs it to stay healthy. Cholesterol plays a vital role in maintaining our cell membranes, and the production of vitamin D and bile acid; it is used to produce many hormones, such as testosterone and oestrogen.

So why all the bad press? Well, there are two types of cholesterol – good cholesterol and bad cholesterol. And too much bad cholesterol gets stuck to the walls of your arteries, increasing your risk of heart disease or stroke.

You can read more on cholesterol in our what is total cholesterol? blog. 

Good cholesterol vs bad cholesterol

As cholesterol travels around our bodies in the blood and is bound to small proteins called lipoproteins, high-density lipoproteins (HDL) remove cholesterol from our tissues and take it back to the liver to be recycled. Because of this helpful role in the body, HDL is often referred to as good cholesterol and it offers a protective role.

In contrast, low-density lipoproteins (LDL) carry cholesterol from the liver to our tissues, depositing it on our artery walls. Too much LDL leads to fatty plaques developing, which block the blood vessels and increase the risk of cardiovascular disease and stroke.

Although high levels of LDL in our bodies have a negative effect, these proteins are still important for our health as, at low levels, they are useful in the production of vitamin D and steroid hormones.

What affects cholesterol levels in the body? 

Key risk factors for developing high cholesterol:

  • Smoking
  • Not being active
  • High alcohol intake
  • Family history of heart disease
  • Eating a lot of saturated or trans-fat
  • Having too much body fat, especially around your middle

Cholesterol, hypercholesterolemia, and thyroid disease

As well as diet and lifestyle, our cholesterol levels can also be affected by certain conditions such as familial hypercholesterolemia and thyroid disease.

Hormones produced by our thyroid gland play a major role in regulating metabolism and aid in the breakdown of fats, including cholesterol. So, an underactive or overactive thyroid gland can affect the body’s ability to process cholesterol.

Hypothyroidism can also lead to hypercholesterolemia, which is the increase of LDL cholesterol in the body. If you are experiencing symptoms of a thyroid-related condition, then a thyroid-related blood test can provide a simple way to check your thyroid function.

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Is it possible to lower cholesterol?

It is possible to get your cholesterol back to a healthy level through healthy swaps. For instance, you can lower your cholesterol by making minor changes to your diet and lifestyle choices [2].

Foods containing saturated fats, including red meat, cheeses, fats, and oils, contain high amounts of cholesterol. Whereas animal products and plants do not contain cholesterol. Eating fresh fruit, vegetables, seeds, nuts, and whole grains can help to lower cholesterol. Reducing alcohol intake and exercising more also help to lower the risk of cholesterol-related diseases.

Ways to lower cholesterol:

  • Changing what you eat
  • Reducing how much alcohol you drink
  • Being more active
  • Stopping smoking

How can I check my cholesterol levels?

Because there are no obvious signs of high cholesterol in our bodies, the only way to check cholesterol is through a blood test.

With an at-home Cholesterol Blood Test, you can measure your levels of triglycerides, LDL and HDL cholesterol, as well as determine your risk of heart disease based on the ratio of total cholesterol to HDL cholesterol. You'll find out whether you have an ideal cholesterol level (where it falls within the normal/healthy range) or whether your cholesterol level is out of range. 

Our cholesterol test also checks for non-HDL cholesterol, which is calculated by subtracting your HDL cholesterol result from your total cholesterol. It, therefore, includes all the non-protective and potentially harmful cholesterol in your blood and is an effective marker for cardiovascular risk.


1. https://www.england.nhs.uk/2021/09/nhs-cholesterol-busting-jab-to-save-thousands-of-lives/

2. https://www.bhf.org.uk/informationsupport/support/reducing-your-high-cholesterol


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